Dioxide Materials was founded in 2009 in

Champaign, Illinois Champaign ( ) is a city in Champaign County, Illinois, United States. The population was 88,302 at the 2020 census. It is the List of municipalities in Illinois, tenth-most populous municipality in Illinois and the fourth most populous city in ...

, and is now headquartered in

Boca Raton, Florida Boca Raton ( ; ) is a city in Palm Beach County, Florida, United States. The population was 97,422 in the 2020 United States census, 2020 census and it ranked as the 23rd-largest city in Florida in 2022. Many people with a Boca Raton Address, ...

. Its main business is to develop technology to lower the world's

carbon footprint A carbon footprint (or greenhouse gas footprint) is a calculated value or index that makes it possible to compare the total amount of greenhouse gases that an activity, product, company or country Greenhouse gas emissions, adds to the atmospher ...

. Dioxide Materials is developing technology to convert

carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...

, water and

renewable energy Renewable energy (also called green energy) is energy made from renewable resource, renewable natural resources that are replenished on a human lifetime, human timescale. The most widely used renewable energy types are solar energy, wind pow ...

into

carbon-neutral Global net-zero emissions is reached when greenhouse gas emissions and Greenhouse gas removal, removals due to human activities are in balance. It is often called simply net zero. ''Emissions'' can refer to all greenhouse gases or only carbon diox ...

gasoline Gasoline ( North American English) or petrol ( Commonwealth English) is a petrochemical product characterized as a transparent, yellowish, and flammable liquid normally used as a fuel for spark-ignited internal combustion engines. When for ...

(petrol) or

jet fuel Jet fuel or aviation turbine fuel (ATF, also abbreviated avtur) is a type of aviation fuel designed for use in aircraft powered by Gas turbine, gas-turbine engines. It is colorless to straw-colored in appearance. The most commonly used fuels for ...

. Applications include CO₂ recycling,ARPA-E Brief: ''Converting CO₂ Into Fuels and Chemicals'

/ref> sustainable fuels production and reducing curtailment of renewable energyLori Bird, Jaquelin Cochran, and Xi Wang, ''Wind and Solar Energy Curtailment: Experience and Practices in the United States'', NREL Report NREL/TP-6A20-60983, March 2014 (i.e. renewable energy that could not be used by the grid).

Carbon Dioxide Electrolyzer Technology

Carbon Dioxide electrolyzers are a major part of Dioxide Materials' business. The work started in response to a

Department of Energy A ministry of energy or department of energy is a government department in some countries that typically oversees the production of fuel and electricity; in the United States, however, it manages nuclear weapons development and conducts energy-rela ...

challenge to find better catalysts for

electrochemical reduction of carbon dioxide The electrochemical reduction of carbon dioxide, also known as CO2RR, is a process that converts carbon dioxide (CO2) to more reduced chemical species using electrical energy. CO2RR can produce diverse compounds including formate, carbon monoxid ...

.A. Bell et al. Basic research needs catalysts for energy, DOE PNNL-17214 At the time the

overpotential In electrochemistry, overpotential is the potential difference (voltage) between a half-reaction's thermodynamically determined reduction potential and the potential at which the redox event is experimentally observed. The term is directly r ...

(i.e. wasted voltage) was too high, and the rate too low for practical applications. Workers at Dioxide Materials theorized that a bifunctional catalyst consisting of a metal and an

ionic liquid An ionic liquid (IL) is a salt (chemistry), salt in the liquid state at ambient conditions. In some contexts, the term has been restricted to salts whose melting point is below a specific temperature, such as . While ordinary liquids such as wate ...

might lower the overpotential for

. Indeed, it was found that the combination of two catalysts,

silver nanoparticles Silver nanoparticles are nanoparticles of silver of between 1 nm and 100 nm in size. While frequently described as being 'silver' some are composed of a large percentage of silver oxide due to their large ratio of surface to bulk silv ...

and an

solution containing equal volumes of 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM-BF4) and water, reduced the overpotential for CO₂ conversion to carbon monoxide (CO) from about 1 volt to only 0.17 volts.Brian A. Rosen, Amin Salehi-Khojin, Michael R. Thorson, W. Zhu, Devin T. Whipple, Paul J. A. Kenis, Richard I Masel *, ''Ionic Liquid-Mediated Selective Conversion of CO₂ to CO at Low Overpotentials'', Science Vol. 334 no. 6056 pp. 643-644 (2011) . Workers from other laboratories have subsequently reproduced the findings on many metals, and with several ionic liquids. Dioxide Materials has shown that a similar enhancement occurs during

alkaline water electrolysis Alkaline water electrolysis is a type of electrolysis that is characterized by having two electrodes operating in a liquid alkaline electrolyte. Commonly, a solution of potassium hydroxide (KOH) or sodium hydroxide (NaOH) at 25-40 wt% is used. Th ...

Zengcai Liu, Syed Dawar Sajjad, Yan Gao, HongzhouYang. Jerry J.Kaczur. Richard I.Masel, ''The effect of membrane on an alkaline water electrolyzer'', International Journal of Hydrogen Energy 42(50), 29661-29665 (2017) and the hydrocarboxylation of acetylene ("

Reppe chemistry Walter Julius Reppe (29 July 1892 in Göringen – 26 July 1969 in Heidelberg) was a German chemist. He is notable for his contributions to the chemistry of acetylene. Education and career Walter Reppe began his study of the natural sciences Un ...

").

At this point, there is still some question about how the imidazolium is able to lower the overpotential for the electrochemical reduction of carbon dioxide. The first step in the electrolysis of CO₂ is the addition of an electron into the CO₂ or a molecular complex containing CO₂. The resultant species is labeled "CO₂¯" in the figure on the left. It requires at least an electron-volt of energy per molecule to form the species in the absence of the ionic liquid.Chemistry Views (Elsevier) Converting CO₂ with Less Energy That electron-volt of energy is largely wasted during the reaction. Rosen at al postulated that a new complex forms in presence of the ionic liquid so that 1 eV of energy is not wasted. The complex allows the reaction to follow the green pathway on the figure on the right. Recent work suggests that the new complex is a

zwitterion In chemistry, a zwitterion ( ; ), also called an inner salt or dipolar ion, is a molecule that contains an equal number of positively and negatively charged functional groups. : (1,2- dipolar compounds, such as ylides, are sometimes excluded from ...

Other possible pathways (i.e. non-zwitterions) are discussed in Keith et al. Rosen at al. Verdaguer-Casadevall et al. and Shi et al.

Sustainion Membranes

Unfortunately, ionic liquids were found to be too corrosive to be used in practical carbon dioxide electrolyzers. Ionic liquids are strong solvents. They dissolve/corrode the seals, carbon electrodes and other parts in commercial electrolyzers. As a result, they were difficult to be used in practice. In order to avoid the

corrosion Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engine ...

, Dioxide Materials switched from ionic liquid catalysts to catalytic anion exchange polymers.R. I. Masel, Qingmei Chen, Zengcai liu, Robert Kutz, ''Ion Conducting Polymers'', US patent 9580824 A number of polymers were tested and the imidazolium functionalized styrene polymer shown in the figure on the right showed the best performance. The membranes were trade named Sustainion. The use of Sustainion membranes raised the current and lifetime of the CO₂ electrolyzer into the commercially useful range.R.F. Service, ''Two new ways to turn ‘garbage’ carbon dioxide into fuel'' Science, Sept 1, 2017 Steven K Ritter, ''CO₂ Electrolyzer Nears Commercialization'', C&E News, Volume 93 Issue 13 , p. 30 . March 30, 2015Mark Harris, ''The entrepreneurs turning carbon dioxide into fuels'', The Guardian, 14 Sept 2017 ''SAVVY: Turning Carbon Dioxide into products'' New Straitus Times, Dec 3, 2017. Michael Foertsch, These methods turn CO2 into cheap energy, Wired, Sept 24, 2017 Sustainion membranes have shown conductivities above 100 mS/cm under alkaline conditions at 60 °C, stability for thousands of hours in 1M KOH, and offer a physical mechanical stability that is useful for many different applications. The membranes showed a lifetime over 3000 hours in CO₂ electrolyzers at high current densities. More recent research has noted that a cell membrane that has an optimized cathode has the capability of running for up to 158 days at 200 mA/cm² .Zengcai Liu et al 2018 J. Electrochem. Soc. 165 J3371 DOI 10.1149/2.0501815jes

References

{{Authority control Electrochemical engineering Chemical companies of the United States Companies based in Boca Raton, Florida Carbon dioxide Climate change